1. Field of the Invention
The present invention relates to a technology relating to S-band satellite digital broadcasting that is distributed by making use of a geostationary satellite SAT launched into a geostationary orbit, for instance, over the equator, and more specifically to a cradle, a receiving terminal and a receiving method for receiving broadcasting by bringing a portable receiving terminal in, for instance, an automobile.
2. Description of the Related Art
Japanese Patent Application publication No. 10-308695 is a document that discloses a system for implementing S-band satellite broadcasting. According to the publication, a receiving terminal to be used in S-band satellite digital broadcasting receives an S-band signal that is transmitted from a geostationary satellite and further relayed through reproducing type relays (gap-fillers; hereinafter simply referred to as GFs) disposed on the earth (in particular on the tall building). The receiving terminal has antennas that directly receive an RF signal and a main body that demodulates the RF signal and decodes into a video audio signal. In order that the receiving terminal receives the decoded video audio signal, all these elements are considered to set fixed in a vehicle, however, a palm-top type portable receiving terminal is also available. However, in a case of broadcasting service being permitted to receive by making a service contract with a broadcasting enterprise, it is preferable for the contractant to be able to enjoy the broadcasting service wherever he/she is. Accordingly, a compatible portable receiving terminal that can be used in an automobile is in demand.
In this connection, in a case of the portable receiving terminal being used in a vehicle, in the GF area, an antenna built into the portable terminal can receive S-band broadcasting waves. However, in an area outside of the GF area where directs wave from a satellite is received, the built-in antenna of the portable receiving terminal used in a vehicle becomes incapable of receiving the S-band signals because the electromagnetic waves is being cutoff by a roof of the vehicle (generally made of metal).
Furthermore, demands for video and audio presentations that make use of an audio environment through a car stereo and display of a car navigation system to be used in the vehicle are also strong. However, in a case that the portable receiving terminal is being brought into a vehicle as it is and used, one cannot cope with these demands.